Gas-oven



A. H. KOHLMEYER.

GAS OVEN. APPLICATION FILED IAN. 29, 19Ie.

RENEWED APR. 5. i920.

Patented N 0V. 9, 1920.

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APPLICATION FILED JAN. 29. I9I6 A. H. KOHLIVIEYER.

GAS VEN.

RENEWED APR. 5. 1920.

Patented Nov. 9, 1920.

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Patented Nov. 9, 1920.

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GAS OVEN. APPLICATION FILED IAN.29, I9Ie. 1,358,217.

' A. H. KOHLMEYER.

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GASOVEN. APPLCATIQN FILED IAN. 29, 1916. RENEWED APR. 5,1920. 1,358,217.

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AUGUST H. KOHLMEYER, OF DETROIT, MICHIGAN.

y Gas-OVEN.

Specification of Letters Patent.

Patented Nov. 9, 1920.

Application filed January 29, 1916, Serial No; 75,173.V vRenewed April 5,1920. Serial No. 371,478.

T 0 allzu/10m t may concern:

Be it known that l, AUGUST H. KoHL- MEYER, a. citizen ofthe United States, residing at Detroit, Michigan, have invented a certain new and useful Improvement-in Gas Ovens, of which the following is a full, clear, and exact description, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, forming part of this specification.

Hy invention relates generally to ovens and more particularly to ovens which are used for culinary purposes and which are heated by the combustion of gas.

The principal objects of my invention are, to generally improve upon and simplify the construction of the oven disclosed in Patent No. 1,135,700 issued to me April 13, 1915, and further to provide an oven having two chambers or compartments, one of which is particularly adapted to be used after the manner of the well-known tireless cooker.

Further objects of my invention are to provide an improved thermostatic control for the temperature in one of the oven chambers or compartments; to provide comparatively simple and easily adjusted means for controlling and regulating the action of the thermostatic control devices; to provide a two-compartment oven with a single air inlet opening and with a single damper controlled outlet; to provide means for regulating the action of the outlet damper in proper relation to the opening of the valve controlling the flow of gas to the burner vof the lower oven; to provide means whereby the damper controlling the oven outlet and the gas controlling valve for the upper oven are simultaneously and automatically closed when the temperature in said oven has reached a predetermined degree; to provide means for controlling the circulation of heated air through the oven so as to obtain the greatest possible degree of efhciency from a given quantity of gaseous fuel, and further to provide a comparatively simple construe tion which. possesses a comparatively high degree of eiiciency and which is especially effective in the utilization and conservation of the heat produced by the combustion of the fuel gas.

With the foregoing and other objects in view, my invention consists incertain novel y features of construction and arrangement of ,paits, hereinafter more fully described,

claimed and illustrated in the accompanying drawings, in which- Figure 1 is a sectional view taken vertically through the oven "a short distance to the rear of the front wall thereof with portions ofsaid front wall in elevation.

Fig. 2 is a vertical section taken approxi* mately on the line 2-2of Fig. l.

Fig. 3 is a horizontal section taken approximately on the line 3 3 of Fig. 1, with parts on the interior of the oven broken away.

Fig. 4 is a horizontal section taken approximately on the line 4.-4 of Fig. 1, with parts on the interior of the oven broken away.

Fig. 5 is an enlarged rear elevational view of the upper left hand corner of the oven.

Fig. 6 is a vertical section taken approximately on the line 6 6 of Fig. 5, with parts broken away.

Fig. 7 is a perspective view of the thermostaticl member made use of in my improved oven.

Fig. 8 is a front elevational view of a portion of the thermostatic member, with parts broken away and in section.

, Fig. 9 is an'enlarged horizontal section taken approximately on the line 9 9y of Fig. 6.

Fig. 1() is an enlarged elevational view taken approximately on the line 10-10 of Fig. 5. l

Fig. 11 is a plan view of a modified form of the thermostat.

Fig. 12 is a plan view of a further modified form of thermostat. l

As illustrated in the drawings, the body 10 ofy my improved oven is substantially rectangular in form with double walls, top and bottom, and having the space between said double walls packed with a suitable heat insulating material 11.

The space within the rectangular body of the oven is divided by a horizontally disposed partition hereinafter more fully described, so as to form lower and upper compartments 12 and 13, respectively.

The front wall of the body is provided with suitable openings which provide access to the oven compartments, said openings being closed by lower and upper doors 14 and 15, respectively. These doors are preferably constructed with double walls and packed with a suitable heat .insulating materialv Formed in tl-e bottom of the body is an air inlet opening 16 in which is positioned an ordinary gas burner 17, the same being utilized primarily for heating the lower compartment 12.

Removably located in a space 18 between the upper and lower compartments is a palr of burner tubes 19 which are for the purpose of heating the upper compartment 13.

Positioned on these burner ltubes adjacent to the air inlet openings thereof are shields or baffle plates 19a which are for the purpose of preventingl back firing or the passage of flames from the jet openings of said burner tubes to the air and gas inlet openingsl A gas supply pipe 20gis located on the rear sideof the oven body and connected thereto are branch pipes 21 and 22 which lead respectively to burners 17 and 19. Located in branch pipe 21 is aout-off valve 23 and located in branch pipe 22 isacut-otf valve 24 and a valve 25, which latter isprovided with a suitable handle so as to be manually operated.

l Removablv positioned within the lower4 .compartment 12 and located adjacent to the side walls thereof are vertically-disposed plates 26, the same being slotted or perforated as designated by 27 and provided with inwardly projecting flanges 28, which latter are for the purpose 'of supporting a rack or pan at differentelevatins within said lower compartment.l The upper endsof these plates 26 are extended horizontally outward as designated by 26a and the outer ends of said extensions bear directly `against the inner. faces of the side walls of the lower .compartment, thus closingthe spaces between said plates 26 and the side Walls at their upper ends. The lower ends of the plates 26 terminate a short distance above the bottom of the compartment 12 and supported by said lower ends is ahorizontally disposed removable plate 29, the same being provided nearvits edges with slots or apertures .30.

This plate 29 is of such length so that its front and rear edges engage directly against the inner faces of the` corresponding walls of the lower compartment, and thus the diy rect draft of heated air from'burner 17 is caused to pass to the sides of the plate 29 and then pass upward through the spaces bewen plates 26 and the side walls of the oven 0 y 1 Removably positioned on the bottom of the oven body and directly over the opening 16 is a heat and flame deeeting plate 31 and removably positioned on top of this plate and spaced apart therefrom is a perforated heat distributing plate 32. Leading downward through plates 29, 32 and 31, from a point near the opening normally closed by i door 14 to the lower burner 17, is a( lighting tube 33.

Removably positioned between the upper ends of plates 26 and immediately below the space 18 occupied by burner tubes 19 is a heat delecting member 34, the same being formed of double walls, the space between which is packed with a suitable heat insulating material and positioned on the front and rear edges of this plate are handles 35;

These handles in addition to serving as means for removing and inserting the plate 34, perform the functions of stops and spacingmembers inasmuch as the rear one of said handles bears against the inner face tubes 19 vis a horizontally disposed perforated plate 36, the front and rear edges of which engage respectively the inner faces' of`the-front and rear walls of the oven body, said plate being slightly' narrower in width than the space within the upper .compartment 13 so that the greater portion of the air heated by burners 19 is caused to pass laterally beneath said plate and thence upwardly from the side`edges thereof.

Removably positioned on top of plate 36 is a plate 37 whichlserves as a bottom for the upper compartment 13.

Removably positioned on the sides of plate 36 are vertically disposed plates 38, the same being 'spaced apart from and occupying positions parallel with the inner faces of the side walls of the upper compartment and formed integral with and projecting outwardly from each of said plates is a series of pins or fingers 39. Formed on 0r fixed to these plates and projecting inwardly there-` from are horizontally disposed ribs -or flanges 40 which serve as ledges to support .E

racks or pans at various elevations within compartment 13. The length of the plates 38 is such that their front and rear edges bear respectively againstthe front and rear walls of compartment 13.

Positioned on the upper ends of plates 38 and occupying a plane a short distance below the top of the compartment 13 is a horizontally disposed plate 41 which is provided on its upper side with a field of upwardly projecting pins or fingers 42 and with a double row of upwardly projecting inclined deflector plates or ribs 43. These deflector plates orribs extend from pointsA near the side edges of plate' 41 to points adjacent to the center thereofjand are for the purpose of `causing the heated air which passes upwardly in the spaces between the plates 38 and the side walls of compartment 13 to travel to the center of the space between plate 41 and the top of said compartment before leaving said compartment 13 through vthe exit opening. This opening or outlet, designated by the numeral 44, is formed through the upper portion of the rear wall of the oven body and leads from the space between plate 41 and the" top of compartment 13. The outer end of this outlet isl normally closed by a damper 45 in the form of a plate and which is hinged and mounted for sliding movement upon a rod 46, which latter is supported in any suitable manner on the back wall of the oven.

Fulcrum'ed on the rear side of the oven and adjacent to one end of the damper 45 is a bell crank 47 and pivotally connected to the end of one of the arms thereof is a rod 48, the end of which is pivotally connected to a pin 49, which latter is seated in and projects from said damper. The'connections between the ends of this rod 48 and bell crank 47 and pin 49 are relatively loose in order to permit damper 45 to swing outg wardly into full open position without shifting the position of bell crank 47.

Pivotally connected to the end of the other arm of this bell crank is the upper end of a rod 50, the lower end of which is pivotally connected Ato an arm 51, which is fixed to the stem of valve 23.

Fulcrumed on the rear side of the oven a short distance below damper 45 is a bell crank 52 and pivotally connected to one of the arms thereof is the lower end of a rod 53, the upper end of which is pivotally connected to a bracket 54 which'projects from the central portion of damper 45. The con nections between the ends of this rod 53 and bracket 54 and bell crank 52 are relatively loose so las to permit the damper 45 to move lengthwise upon supporting rod 46 without affecting the position of bell crank 52.

Pivotally connected to the opposite end of bell crank 52 is one end of a rod 55, the other end of which is pivotally connected to an arm 56, which is fixed to the stem of valve 24. The free end4 of this arm 56 is provided with a rearwardly extending lug 57, the upper outer corner of which yis pointed as designatedby 58.

Pivotally mounted on the rear side of the oven is a vertically disposed arm 59 and associated with the pivot point thereof is a spring 60 which is arranged to normally exert outward pressure on that portion of the arm below the pivot point.

livotally mounted in the lower end of this arm is a roller 61- which is adapted to engage the point 58 on lug 5 7 when arm 56 occupies a horizontal position. Seated in the `lower end of arm 59 and below'the roller .Seated 1n adjusting screw 64, the same carrying on its inner end a disk 65.

The thermostat utilized in connection with my improved oven occupies a position ,on the rear wall of compartment 13 adjacent to plate 41, said thermostat being in the form of a-horizontally disposed bar 66 composed of two or more plates of different metals, the same having variableexpansive movement under the same degree of heat and one end of this thermostatic lmember isyprovided with a plate 67 having knifeedged bearing fingers 68 which occupy bearing loops 69. These bearing loops are formed on a bracket 70 which is fixed to top plate 41.

The free end. of the thermosta'tic bar bears loosely against a bracket 71, the same being fixed to top plate 41. Fixed to the thermostatic bar ata point near its center is a plate 72 providedwith bearing loops 73 and positioned therein are knife-edged bearing fingers 74, the same being formed on. the end of a horizontally disposed arm 78.

When in proper position, this arm lies directly in front of the free end of thermostatic bar 66, as illustrated in Fig. 7 and the free end of this arm carries a pin 78a which is adapted to slide freely through an aperture 79 formed in the rear wall of the oven body. The outer end of this pin is adapted to engage against disk 65.

The members of the pairs of bearing loops 69 and 73 are reversely arranged with respect to each other so as to permit the thermostatic member 66 and bar 78 to be readily removed or placed in operative position.

Pivotally securedto a bracket 80 on plate 41 is a depending link 81 to the lower end of which is pivotally connected one end of a loop or stirrup 82. Screw-seated in the opposite end of this stirrup is the threaded end of a push rod 83, the same carrying a lock nut 84 and thev rear end of said rod occupies a position between a pair of lugs or pins 85 which project upwardly from a horizontally disposed flange 85a on arm 7 8.

Located in the front wall of the oven body above the upper door opening is a tubular housing 86, which is provided with an internal threaded portion which is engaged by thethreaded portion of a rod 87. This rod is preferably constructed with a left hand thread and its inner end is adapted to engage directly against the front side of link 81.

Fixed on the outer face of the front wall of the oven body above the cylindrical memthe upper end of arm 59 is an A housing 91, which is located in the righthand side wall of the oven body and the right to move its outer end along the scale,

rod 87 will be partially rotated and by reason of the engagement of the threaded portion of said rod, with the threaded portion of member 86, said rod will be drawn a slight distance outwardly away from link 81. As this link 81 is pivotally connected to bracket 80 at a point in front of the point of contact between it and the rear en d of rod 87, said link will by gravity swing forwardly. thereby drawing push rod 83 a corresponding distance forward. It will be understood that the lengthwise movement thusimparted to rod 87 as the same is rotated is comparatively 'slight and depends on the pitch of thread thereon;

Connected to the Vstem of valve 2.4 is a rod 90, the same extending through a tubular forward end of this rod, which terminates on the front wall ofthe oven is .provided with an operating handle 92. This handle operates immediately over a plate 93 which is fixed on the front of the oven, said plate bea-rin the words Upper oven On and if. v

Formed integral with the plate 93 and projecting a short distance into the right hand wall of the oven and in alinement with the tubular member 91 is a short tubular member 93, and positioned therein is a torsional spring 94, one end of which is fixed to rod 90 and the other end to said member 93a.

This spring is adapted to lpartially rotate rod 90 to close valve 24 when the Apoint 58 on the end of arm 56 is released from roller 61, which latter is carriedl by arm 59.

Fixed to the stem of valve 23 is the rear` end of a rod 95 which extends through a tubular housing 96, the same being located in the right hand side wall of the oven body.

The end of this rod at the front of the oven is provided with an operating lever 97, the

same, operating over a disk 98 which is marked with the words Lower oven l and which is provided with anj arcuate scale nunibered from 1 to 8 inclusive.

The operation of my improved 'oven'is as follows: l f 3 Then it is desired to use the lower oven compartment 12, handle A97, which normally loccupies a vertical position as seen in Fig. 1v

fis engaged and moved Ytoward the right hand with the resultthat rod. 95 is rocked, thereby opening valve-'23 and swinging-arm r'51 downward. 3 y

lArcuate scale on plate 98 serves as a -guide Fixed on the forward end of rod 87k for regulating the degree of movement of this hand lever 97 and consequently the degree of opening movement imparted to the valve 23. y

As valve 23 is thus opened, gas from main supply pipe 2() will pass through branch pipe 21 to burner 17 at which point it is ignited and the flame is directed upwardly to impinge against deiector plate 31.

Simultaneous with the opening of valve 23 and swinging movement imparted to arm 51, rod 50 will be drawn downward, thereby actuating .bell crank 47 and shifting link 48, thereby sliding damper 45 along rod 46 so as to uncover a portion of vent or outlet 44.

This opening movement of valve 23 has no'eti'ect whatever upon Avalve 24, that is, it does not tend to open said valve 24 for the relatively loose connections between rod 53 and bell crank 52 and lug 54 on damper 45 permit said damper to move its full stroke lengthwise upon rod 46 without imparting any movement to bell crank 52 and the connections therefrom to valve 24.

It .will be understood that the degree of openlng movement imparted to damper 45 correspondsv with, and is in proper relative proportion to the opening movement imparted to valve 23, andl consequently if said valve 1s opened to permit a relatively small iow of gas to Iburner A17 damper 45 will be shifted so as to uncover only a comparatively small portion of outlet 44, and thus the circulation of heated air and gas from burner 17 through the oven to the outlet will be comparatively slow.

he greater portion ofthe heated air from i burner 17 passes laterally beneath plates 32 and 29 and thence upward through the spaces between plates 26 and the side walls of the lower compartment, and as the upper ends of Athese spaces are closed, the heated air is caused to pass through the slots or openings 27 in plates 26, after which said heated air passes'both forwardly and rearwardly beneath plate 34, from whence it dlscharges at the front and rear ends of saidplate upwardly into the space 18 occu- 'outlet 44. The lower'compartment 12 is primarily intended for use for the purpose of baking bread, cakes, pies and the like, and during the time required for the baking operations, theheated air after passing through and around the lower compartment passes uplward through perforated plate 36, also through the spaces to the sides of the upper compartment 13, thereby heating the 'plates 38 and the fingers or projections 39 thereon and likewise heating top plate 41 and the fingers or projections 42 thereon. Thus a considerable degree of heat from the lower burner is conserved and retained by the bottom, side and top walls of the upper compartment and the heat thus retained can be utilized for the subsequent cooking of food in the upper compartment.

F or instance z-If a temperature of approximately 400 degrees is maintained for a considerable period of time in the lower compartment 12 to effect baking operations, a slightly lower temperature will be produced in the upper compartment 13 and this temperature can be utilized for a considerable `period of time after valve 23 has been closed to shut off Vthe flow of gas to burner 17 and'which action swings damper 45 into position to close the outlet 44.

Yhen damper 45 is closed, circulation ceases through the oven, and owing to the fact that the outer walls of the oven body are insulated against the radiation of heat, the comparatively high temperature is retained for a considerable period of time within compartment 13 and said compartment can be utilized as a tireless cooker, thus gaining the advantage of heat which'would otherwise pass from the oven to the chimney or other outlet.

In the event that it is desired to produce and maintain a much higher degree of temperature in compartment 13, the upper burners 19 are lighted and in a comparatively short time the required high degree of temperature is produced, owing to the fact that compartment 13 is already heated to a considerable degree.

When it is desired to use upper compartment 13 for cooking operations which require a comparatively high degree of heat and where it is desired to automatically regulate the temperature within said compartment. the operator engages handle 92 and swings the same toward the' right hand, thereby opening valve 24 and swinging arm 56 downward. consequently positioning the point 58 on lug 57 carried by said arm beneath roller 61 as'illustrated in Fig. 10. This engagement of the point ,58 With roller 61 maintains the rod 90 in its rocked position against the tendency of spring 94 to return said rod to its normal position.

As valve 24 is thus opened, gas will pass through branch pipe 22 to upper burners 19 and the same are lighted through openings 36a. The shields 19a located on the ends of the burner tubes 19 prevent back firing or the passage of flames from the burner tubes to the air and gas inlet openings at the rear ends of said tubes.

When the upper burner tubes are utilized,

rocking rod 90 and simultaneously the air inlet openings at the rear ends of the upper burner tubes.

As rod is rocked as just described and arm 56 is swung downward to engage point 58 beneath roller 61, link 55 will beshifted so as to rock bell crank 52, thereby pulling rod 53 downward, and consequently swinging damper plate 45 outwardly away from outlet 44.

This opening movement of valve 24 has no tendency to open valve 23 by reason of the fact that the relatively loose connections between the. ends ouf rod 48 and bell crank 47 anddamper 45 permit the latter to swing into full open position without actuating said bell crank 47 and the connections therefrom to valve 23.

The movement of handle 92 is approximately ninety degrees and such movement results in a full opening of valve 24. Finger 89 vis now turned toward the right over plate 88 until the end of said linger is at the scale mark which corresponds to the degree of temperature which it is desired to produce within upper compartment 13 and as the finger is thus actuated, rod 87 will be partially rotated and owing to the engagement of the threaded portion thereof with the threaded portion of member 86, said rod will move forward a short distance and link 81 will by Y gravity swing a corresponding distance forward in following said rod 87.

The operation just described sets the thermostatic control devices so that the same will operate to effect a closing movement of valve 24 and likewise a closing movement 105 of damper 45 when a predetermined high degree of temperature has been developed within compartment 13, it being understood that the thermostatic bar will act or bow outwardly for a certain distance under rising temperature before the various parts of the control mechanism move a suiicient distance to cause the rear end of push rod 83 to act as a fulcrum for bar 78. i

Under normal conditions, the .thermostatic bar 66 is approximately straight and the rear end of push rod 83 occupies a position on ange 85a between lugs 85.` i vAs the temperature rises within upper compartment 13, as a result of the heat from the gas ignited at -burners 19, the central portion of thermostatic bar 66 will gradually bow inward or away from the rear wall of upper compartment due to the variable expansive action of the layers of dierent metall forming said member, with the result that plate 72 carrying one` end of bar 7 8 will be slowly moved inward or toward the point of push rod 83.

As the forward bowing movement of thermostatic bar 66 continues,-the rear end comparatively short distance, and conse-v quently causing roller 66 to ride over point v 58 on lug 57 of arm 56.

, bearings at the As this action takes place, the power stored in torsional spring 94 will act to return rod 90 and parts carried thereby to normal position,and consequently valve 24 will be closed and simultaneously damper plate 45 will be 'swung upward to close loutlet 44.

As valve 24 is thus closed, the gas to burners 19 is cut oil and as outlet 44 is closed, circulation of heated air through the oven will cease and the comparatively high de-- gree of temperature within compartment 13 will be maintained for a considerable period of time. During this time,. th e upper compartment can be utilized after the manner of a reless cooker, thereby taking advan tage of the comparatively high temperature within said compartment, thus materially increasing the efficiency of the oven and thereof.

It will be noted that the thermostatic member 66 and bar 78 have knife-edged points where they are supported and further that the push pin 78?1l has a comparatively small bearing through the rear wall of the oven.

By virtue of such construction, friction during the movement of the parts is re-A duced to a minimum with the result that the thermostatic control is very sensitive in action.

The manner of mounting thermostatic member 66 and bar 78 permits their ready removal or insertion inthe event of adjustments or repairs.

The relative lpositions of the various parts of the automatic regulator can be readily adjusted by screwing push rod 83 into or out of the yoke 82, by screwing the bolt 64 back' ward or forward with respect to the arm 59 to change the psition of disk 65, and by screwing the adjusting screw 62 to regulate the degree of engagement of point 58 with roller 61.

There'isl a sulicient degree of flexibility between the `ends of rods 48 and 53 with the damper plate 45 to permit freedom of movement between Said parts when said plate is either swung outwardly or shifted lengthwisel upon the supporting rod 46.

Manually operated valve-2 5 provides means for controlling thevolume of gas delivered to upper burners 19 and likewise said valve provides means for entirely closmaterially reducing thecost of'operation` the upper portion'of the lower compartment 12 and after lighting the upper burners, a

rack with the article tobe broiled is positioned in the upper portion of the lower oven or directly beneath the upper burners, thus accomplishing the desired result.

My improved means of controlling therelative degree of gas supply to the lower burner and the degree of opening of the outlet for the heated air and burnt gases, permits an accurate regulation and control of the circulation of lheat through the oven and particularly during the baking operations with the result that a Vvery even temperature can be maintained within the lower compartment,f and likewise by such slow circulation the moisture necessary to Support perfect baking operations is retained and absorbed by the objects being baked.

In some instances it may be found `desirable to dispense with the bar 78 Aand to ar-v range the push rod 83 so as to form a ful'- crum against the central portion of said thermostatic bar, as illustrated in Fig. 11.

A further modification of the thermostat is illustrated in Fig. 12, wherein the bar 78 is connected to the free end of thermostatic bar and the fulcrum rod 83 is adapted to engage the central portion of said bar 78.

oven of my improved construction is comparatively simple, requires little or no attention on the part of the operator after the controlvor regulatingparts have been set for proper use, is very economical in point of fuel consumption, and combines the de- -sirable qualities of an ordinary gas heated oven with a tireless cooker.

It will be readily understood that minor changes in the size, form and construction of thevarious parts of my improved oven vcan beimade and substituted for those herein shown anddescribed, without departing from the spirit of my invention, the scope of whichA is` set forth in the appended claims.

I claim: 1. A noven having two chambers, a burner for each of said chambers, a valve for con trolling theflow of gas to each burner, said oven being provided with a single outlet common to both chambers, a damper controlling said outlet, and connections between said damper and both gas control valves, whereby either valve and the damper may be simultaneouslypened or closed.

2. oven having two chambers, a burner for each of said chambers, a valve for controlling the iow of gas to each burnelg'said oven being provided with a. single outlet common to both Chambers, a damper controlling said outlet, connections between said damper and both gas control valves, whereby either valve and the damper may be simultaneously opened or closed, and a thermostat for controlling the closing opv eration of o'ne of said valves and the damper.

8. An oven having two chambers, a burner for each of said chambers, a valve for controlling the flow of gas to each burner, said oven being provided with a single outlet common to both chambers, a damper conytrolling said outlet, connections between said damper and both gas control valves, whereby either valve and the damper may be simultaneously opened or closed, a thermostat for controlling the closing operation of one of said valves and the damper, vand means for controlling the action of said thermostat.

4. The combination with an oven having two chambers and an outlet commonto both chambers, of independent heating means for each chamber, a controlling device for each heating means, a damper for closing the outlet from the oven, manually operable means for simultaneously actuating the heater `controlling device for one of the ovens and the damper, means tendingto reversely aotuate said heater controlling de-I heater controlling device for one of the ovens and the damper, means tending to re'- versely actuate said heater controlling device and means adapted to be actuated by a predetermined degreel of temperature within the said oven chamber for effecting a release of the reversely actuating means to simultaneously impart closing movement to the controlling device and the damper.

6. The combination with an oven having two chambers and an outlet commbn to both chambers, of independent heating means for each chamber, av controlling device for each heating means,a damper for closing the outlet from the oven, manually operable means for simultaneously actuating the y heater controlling device for one of the ovens and the damper, means tending to reversely actuate said heater controlling device, means controlled by the temperature within the oven chamber having the,V outlet for effecting a release of the reversely actuating means to simultaneously impart closing movement to the controlling device and the damper, and means for regulating the action of the temperature .controlled means.

7. The combination with an oven having two chambers and an outlet common to both chambers, of independent heating means for each chamber, a controlling device `for each heating means, a damper for closing the outlet from the oven, manually operable means for simultaneously actuating the heater controlling 4device for one ofthe ovens and the damper, means tending to reversely actuate said heater controlling device, means controlled by the temperature within the oven chamber having the outlet for effecting a release of the lreversely actuating means to simultaneously impart closing movement to the controlling device and the damper, and manually operable means for simultaneously actuating the damper and the heater controlling device for the other oven chamber.

- 8. The combination `with an oveuhaving two chambers and an outlet common to both chambers, of independent heating means for each chamber, a controlling device for each heating means, a damper for closing the outlet from the oven, manually operable means for simultaneously actuating the heater` controlling device for one of the ovens and the damper, means tending to reversely actuate said heater controlling device, means adapted to be actuated by a. predetermined degree of temperature within the. said oven chamber for eii'ecting a release of the reversely actuating means to simultaneously impart closing movement to the controlling device and the damper, and manually operable means for simultaneously actuating the damper and the heater controlling device for the other oven chamber,

9. The combination with an oven having two compartments, and an outlet common to both compartments, of a burner in the lower portion of each compartment, a damper for' the outlet, which damper is arranged to swing outwardly and slide laterally with respect lto said outlet, valves -controlling the ilow of gas to the burners, andy connections between said valves and damper whereby either one of said valves and said damper can be simultaneously opened or closed.

10. The combination with an oven having two chambers andan outlet common to both chambers, of independent heating means for each chamber, a controlling device for each` heating means, a damper for closing the outlet Jfrom `the oven, manually operable means for simultaneously actuating the heater controlling device for one of the ovens and the damper, means tending to reversely actuate said heater controlling device, means 11. An oven having two chambers onedisposed above the other, there being an air inlet opening in the lower portion of the lower chamber and an outlet opening in the lupper portion of the upper chamber, which last mentioned opening is common to both chambers, a burner for each chamber, a valve controlling the supply of fuel to each burner, a damper for closing the outlet from the upper chamber, manually operable means for simultaneously opening each fuel supply valve and the damper, means tending to automatically close the valve for the upper burner and the damper, manually operable means for setting the closing means in operating position, and means controlled by theI temperature within the upper chamber for effecting a release of the setting means to simultaneously close the damper and the fuel supply valve for the upper burner.

12. An oven provided with a pair of chambers, one above the other, a burner for each chamber, a valve controlling the iiowl of gas to each burner, there being an outletfrom the upper portion of the upper chamber, a damper controlling said outlet, sprin actuated -means connected to the valve of t e upper burner for closing the same, an arm coperating with said spring actuated means, a lever adapted to engage lsaid arm when the valve is open, temperature controlled means within the oven for engaging said lever to `release said arm and connections'between the valve of f the lowerburner and the damper, whereby f the latterand the valve for the lower burner are simultaneously opened or closed.

13. An oven provided with a pair of chambers, one above the other, a burner for each chamber, a, valvecontrolling the flow of gas to each burner, there being an outlet from the upper portion of the upper chamber, a damper controlling said outlet, spring actuated means connected to the valve of the upper burner for' closing the same, an arm coperating with said spring actuated means, a lever adapted to engage said arm when the valve is open, temperature controlled means within the oven for engaging said lever to release said arm, means for regulating the action of said temperature controlled means and connections between the valve of the lower burner and the damper, whereby the latter and the valvefor the lower burner are simultaneously opened or closed.

14. An oven, providedl with a pair of chambers, one above the other, a burner for each chamber, a valve controlling the flow of gas to each burner, there being an outlet from the upper portion of the upper chamber, a damper controlling said outlet, spring actuated means connected to the valve of the upper burner for closing the same, an arm coperating with said perature controlled means within the oven for engaging said lever to release said arm, connections from the arm to the damper whereby the latter' is closed simultaneous with the closing of the last mentioned gas ,c control valve, and means connecting the valve of the lower one of the burners and the damper, whereby the latter` and the valve for the lower one of the burners are simultaneously openedv or closed.

15. An -oven provided with a pair of chambers, one above the other, a burner for Ieach chamber, a valve controlling the flow of gas to each burner, there being an outlet rom the upper portion of the upper chamber, a damper controlling said outlet, spring actuated means connected to the /valve of the upper burner for closing the same, an arm spring actuated ymeans, a lever adapted to engage said arm ywhen the last mentioned valve is open, temcoperating with said spring actuated` means, a lever adapted to engage said arm when the last mentioned valve is open, temperature controlled means within the oven for engaging said lever to release said arm,

means for regulating the action of said tem,-

perature controlled means, connections from Y the arm to the damper whereby the latter is closed simultaneous with the closing of the upper one of the gas control valves, and means connecting the damper and the lower one of the gas control valves, whereby the latter and saiddamper are simultaneously opened or closed..

16. An oven having'- two chambers one above the other, the lower chamber being provided with an air inlet opening and the upper chamber with an outlet opening, a vdamper for closing said outlet opening', a burner for heating each chamber, a valve for controlling the supply of fuel to each burner, manually operable means for simul-A taneously opening each fuel supply valve and thedamper, means tending to automatically close the damper and the valve for the burner of the upperchamber, manually op' erable means for setting the closing means 1n operatingposition, and a temperature responsive element located within the upper chamber for automatically releasing the setupper chamber with an outlet opening, a damper for closing said outlet opening, a burner for heating each chamber, ay valve `for controlling the supply of u'el to each burner, manually operable means for simultaneously opening each fuel supply valve and the damper, means tending to automati-- cally close the damper and the valve for the burner of the upper chamber, manuallyoperable means for'setting the closing means in operative position, a temperature responsive element located within the upper chamber for automatically releasing the Setting means to effect a closing movement of the fuel supply valve for the burner of the upper` chamber and for simultaneously closing the damper when a predetermined degree of temperature has been developed within the upper chamber, and means for regulating the action of the temperature controlled means.

18. An oven 4having two chambers, a4

both heater regulating means whereby either of the latter and the damper taneously actuated. l p

In testimony whereof I hereunto ailix my may be simulsignature in the resence of two witnesses,

this 29thday`ofv ecember, 1915.',

' AUGUST H. KOHLMEYER. Witnesses: i' I M. P.- SMITH; M. A. 

